System: Musculoskeletal

Extensor Pollicis Longus

Extensor Pollicis Longus The structure indicated is the extensor pollicis longus muscle of the posterior forearm. The extensor pollicis longus muscle is one of the muscles located in the deep layer of muscles in the posterior compartment of the forearm. There are 5 muscles in the deep layer of the posterior forearm: Supinator Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus Extensor indicis The tendon of the extensor pollicis longus forms the medial border of the anatomical snuffbox. The anatomical snuff box is an anatomical triangle located on the dorsal surface of the hand, it consists of the following …

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extensor pollicis longus

Extensor Hallucis Longus

Extensor Hallucis Longus The structure indicated is the extensor hallucis longus muscle. The extensor hallucis longus is one of the four muscles of the anterior compartment of the leg. The muscles of the leg consist of three compartments: Anterior Posterior Lateral In the anterior compartment are the four following muscles: Tibialis anterior Extensor hallucis longus Extensor digitorum longus Fibularis tertius The muscles of the anterior compartment of the leg serve to dorsiflex the ankle joint, extend the toes and invert the foot, and they are supplied by the deep fibular (peroneal) nerve. Origin: Middle half of medial fibula and interosseous …

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extensor hallucis longus

Extensor Digitorum Brevis

 Extensor Digitorum Brevis The structure indicated is the extensor digitorum brevis muscle. This muscle is the only intrinsic muscle of the foot located on the dorsal aspect, and serves to extend digits 2 to 4. Origin: Superolateral calcaneus Insertion: Base of proximal phalanx of great toe, lateral portion of tendons of extensor digitorum longus of toes 2 – 4. Action: Extension of great toe at MTP joint. Flexion of toes 2 – 4. Innervation: Deep fibular nerve. Learn more about the anatomy of the foot muscles in this tutorial.
extensor digitorum brevis

Gluteus Maximus

Gluteus Maximus The structure indicated is the gluteus maximus. The gluteus maximus muscle is one of the muscles of the gluteal region. The muscles in the gluteal region are divided into a superficial and deep group. There are four muscles of the superficial group: Gluteus maximus Gluteus medius Gluteus minimus Tensor fasciae latae There are 5 muscles in the deep group: Gemellus superior Gemellus inferior Quadratus femoris Piriformis Obturator internus The gluteus maximus muscle is the largest of the gluteal muscles, and is also the largest muscle in the human body. Origin: Posterior surface of ilium, posterior superior iliac crest, …

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gluteus maximus

Superior Articular Process

Superior Articular Process The structure indicated is the superior articular process. There are 33 vertebrae which make up the spinal column: 7 cervical 12 thoracic 5 lumbar 5 fused sacral vertebrae 3-4 fused coccygeal vertebrae The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The superior articular process articulates with the inferior articular process of the vertebrae above. These articulations are known as zyapophysial joints. The articular processes arise from …

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superior articular process

Gluteus Minimus

Gluteus Minimus The structure indicated is the gluteus minimus. The gluteus minimus muscle is one of the muscles of the gluteal region. The muscles in the gluteal region are divided into a superficial and deep group. There are four muscles of the superficial group: Gluteus maximus Gluteus medius Gluteus minimus Tensor fasciae latae There are 5 muscles in the deep group: Gemellus superior Gemellus inferior Quadratus femoris Piriformis Obturator internus Origin: Dorsal ilium between inferior and anterior gluteal lines and edge of greater sciatic notch. Insertion: lateral and superior surfaces of greater trochanter Action: Hip abduction, hip medial rotation (anterior …

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gluteus minimus

Transverse Foramen

Transverse Foramen The structure indicated is the transverse foramen of a cervical vertebra. There are 33 vertebrae which make up the spinal column: 7 cervical 12 thoracic 5 lumbar 5 fused sacral vertebrae 3-4 fused coccygeal vertebrae The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches Transverse foramina are only present in the cervical vertebrae. These foramina allow the passage of the vertebral artery and vein. The vertebral arteries arise …

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transverse foramen

Ischiocavernosus

Ischiocavernosus The structure indicated is the ischiocavernosus muscle. The ischiocavernosus muscle is one of three pairs of muscles in the superficial perineal pouch: Ischiocavernosus Bulbospongiosus Superficial transverse perineal muscles It originates from the inner aspect of the ischiopubic ramus and attaches on either side to the crura of the penis and clitoris. Origin: Ischiopubic ramus – internal aspect Insertion: Crus of penis and clitoris Action: Stabilise erect penis Innervation: Pudendal nerve Learn more about the pelvic floor in this tutorial
ischiocavernosus

Posterior Inferior Tibiofibular Ligament

Posterior Inferior Tibiofibular Ligament The structure indicated is the posterior inferior tibiofibular ligament. The distal ends of the tibia and the fibula are held together by the inferior portion of the interosseous membrane. The interosseous membrane is the membrane which joins the tibia to the fibula along its entire length, separating the leg into anterior and posterior compartments. There are two apertures within the interosseous membrane proximally and distally which allow vessels to pass from one compartment to the other. In addition to the attachment of the interosseous membrane inferiorly between the distal tibia and fibula, this inferior articulation is …

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posterior inferior tibiofibular ligament

Coracoclavicular Ligament

Coracoclavicular Ligament The structure indicated is the coracoclavicular ligament The coracoclavicular ligament is one of the ligaments which stabilises the acromioclavicular joint. The acromioclavicular joint is formed between the acromion of the scapula and the clavicle. It is a small synovial joint that is stabilised by the following ligaments: Acromioclavicular ligament (consists of superior and inferior parts) Coracoclavicular ligaments The coracoclavicular ligaments consist of two parts: Trapezoid ligament Conoid ligament The coracoclavicular ligament, as the name suggests connects the clavicle to the coracoid process of the scapula. Learn more about the anatomy of the shoulder joint in this tutorial.
coracoclavicular ligament